1. Field of the Invention
The present invention relates to a semiconductor package and a method of manufacturing the same and, more particularly, to a thin semiconductor package having a stackable lead frame and a method of manufacturing such packages.
2. Description of the Related Art
In conventional semiconductor production, after forming a plurality of semiconductor chips on a wafer using one of many semiconductor fabrication processes, the completed wafer is thinned by removing backside material and sawn along scribe lines provided between adjacent semiconductor chips to separate the individual semiconductor chips. One or more of the individual semiconductor chips are then assembled in a semiconductor package that can, in turn, be mounted on a mounting substrate or other electronic device such as a printed circuit board (PCB). However, due to the continuing development and miniaturization of electronic devices in recent years, there is a corresponding interest in semiconductor packages that can provide improved performance and/or allow for higher packaging densities.
FIG. 1 is a cross-sectional view illustrating a conventional thin semiconductor package. The conventional thin semiconductor package has a stack of two semiconductor chips 10, both of which are connected to a lead frame 14 using gold bumps 12. The lead frame 14 includes both an inner lead 14a and an outer lead 14b, with the semiconductor chip 10, the inner lead 14a and a portion of the outer lead 14b molded with an encapsulant 16 to protect the semiconductor chip 10 from external impact, moisture and contaminants.
The conventional structure of the thin semiconductor package illustrated in FIG. 1 has certain drawbacks including a tendency for the outer lead 14b to deform as a result of the long length of the lead frame 14 and difficultly in positioning the outer leads 14b in the same plane. That is, when using conventional thin semiconductor package, it is difficult to position and maintain the outer leads 14b in a coplanar orientation.